This chapter discusses the basic principles and applications of thermal remote sensing. The large, synoptic scale of natural hazards presents the ideal opportunity for their observation using remotely sensed observations from orbiting satellites which have a large field of view of the Earth surface–atmosphere system. Satellite imagery, just like imagery from a digital camera, is made up of many pixels which form the smallest portion that can be resolved within an image. Satellites imaging Earth's surface can generally be grouped into one of two categories: polar orbiting satellites, and geostationary satellites. Thermal remote sensing is widely used to monitor clouds and has also shown utility in the observation of other natural hazard phenomena, including heat waves, landslides and floods. The proven utility of thermal remote sensing for monitoring volcanic activity, and potential for earthquakes, is clearly also be useful for landslide monitoring where landslides are induced by these phenomena.